Triangular UIView or UIImageView - ios

Question

I have requirement like below image.
But, i'm confused about how to achieve this? Can i achieved it by using 3 UIImageViews or UIViews. If both then, which one is better? Finally, i have to combine three images & make one from that three images. I should be able to get touch of image too. I have no idea about this. Thanks.

Answer 1

Every UIView has a backing CALayer (accessible by aview.layer).
Every CALayer has a mask property, which is another CALayer. A mask allows to define a see-through shape for the layer, like a stencil.
So you need three UIImageViews, each of them has a different .layer.mask, each of these masks is a different CAShapeLayer whose .path are triangular CGPaths.
// Build a triangular path
UIBezierPath *path = [UIBezierPath new];
[path moveToPoint:(CGPoint){0, 0}];
[path addLineToPoint:(CGPoint){40, 40}];
[path addLineToPoint:(CGPoint){100, 0}];
[path addLineToPoint:(CGPoint){0, 0}];
// Create a CAShapeLayer with this triangular path
// Same size as the original imageView
CAShapeLayer *mask = [CAShapeLayer new];
mask.frame = imageView.bounds;
mask.path = path.CGPath;
// Mask the imageView's layer with this shape
imageView.layer.mask = mask;
Repeat three times.

Answer 2

You can use UIBezierPath and CAShapeLayer to achieve this
Step1: Copy following code
TrImageView.swift
import UIKit
protocol TriImageViewDelegate: class {
func didTapImage(image: UIImage)
}
class TriImageView:UIView {
//assumption: view width = 2 x view height
var images = [UIImage]()
var delegate:TriImageViewDelegate?
override func awakeFromNib() {
super.awakeFromNib()
//add imageviews
for i in 1...3 {
let imageView = UIImageView()
imageView.tag = i
imageView.userInteractionEnabled = true
self.addSubview(imageView)
}
//add gesture recognizer
self.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(TriImageView.handleTap(_:))))
}
//override drawRect
override func drawRect(rect: CGRect) {
super.drawRect(rect)
let width = rect.size.width
let height = rect.size.height
let frame = CGRect(x: 0, y: 0, width: width, height: height)
let pointA = CGPoint(x: 0, y: 0)
let pointB = CGPoint(x: width * 0.79, y: 0)
let pointC = CGPoint(x: width, y: 0)
let pointD = CGPoint(x: width * 0.534,y: height * 0.29)
let pointE = CGPoint(x: 0, y: height * 0.88)
let pointF = CGPoint(x: 0, y: height)
let pointG = CGPoint(x: width * 0.874, y: height)
let pointH = CGPoint(x: width, y: height)
let path1 = [pointA,pointB,pointD,pointE]
let path2 = [pointE,pointD,pointG,pointF]
let path3 = [pointB,pointC,pointH,pointG,pointD]
let paths = [path1,path2,path3]
for i in 1...3 {
let imageView = (self.viewWithTag(i) as! UIImageView)
imageView.image = images[i - 1]
imageView.frame = frame
addMask(imageView, points: paths[i - 1])
}
}
//Add mask to the imageview
func addMask(view:UIView, points:[CGPoint]){
let maskPath = UIBezierPath()
maskPath.moveToPoint(points[0])
for i in 1..<points.count {
maskPath.addLineToPoint(points[i])
}
maskPath.closePath()
let maskLayer = CAShapeLayer()
maskLayer.path = maskPath.CGPath
view.layer.mask = maskLayer
}
//handle tap
func handleTap(recognizer:UITapGestureRecognizer){
let point = recognizer.locationInView(recognizer.view)
for i in 1...3 {
let imageView = (self.viewWithTag(i) as! UIImageView)
let layer = (imageView.layer.mask as! CAShapeLayer)
let path = layer.path
let contains = CGPathContainsPoint(path, nil, point, false)
if contains == true {
delegate?.didTapImage(imageView.image!)
}
}
}
}
Step2: Set the custom class
Step3: Use it